What term is commonly used to refer to the 1920s?

The term commonly used to refer to the 1920s is "Roaring 20s." This phrase captures the vibrant cultural, social, and economic changes that characterized the decade, particularly in North America and parts of Europe. During this time, the aftermath of World War I brought a wave of optimism and prosperity, leading to significant developments in technology, music, fashion, and lifestyle. The decade was marked by the rise of jazz music, the flapper culture, an increase in consumerism, and a general spirit of rebellion against traditional norms. This lively character of the decade is what earned it the descriptor "roaring."

Other terms presented in the options refer to different historical contexts. The Great Depression describes the severe worldwide economic downturn that began in 1929 and lasted through the 1930s. The Dirty Thirties refers specifically to the hardships faced during the Great Depression, particularly in Canada and the United States. The Great War is a term typically used to refer to World War I, which occurred before the 1920s. Thus, "Roaring 20s" is the most accurate term to encapsulate the unique and dynamic essence of that decade.